Country diary

A bright new welcome sign on the gate beckons walkers into Sandy Warren. From the foot of the hill, a track leads up through the trees, curving seductively out of sight into a cutting whose bracken slopes are lit golden brown by the low winter sun. Three years ago another gate stood here, on which a thick metal plate read: "PRIVATE WOODS. KEEP OUT." The spruce plantation was denser and darker then, with wind-blown trees snagged against their neighbours or toppled across the path. The rusting, bottomless carcass of an oil drum stood at the entrance.

I slip through the gate of this new area of RSPB reserve. Towards the top of the steep-sided cutting, spruce trees give way to sweet chestnut. Six or seven thick trunks grow from some of the coppiced stools; others have long ceased to be productive, the stools girdled with barren stumps.

The path crests the brow of Redstone Hill, but immediately dips into a circular hollow about 15 feet deep and 100 feet wide. The estate map of 1851 shows a disused quarry marked, but this is no more than an ice-cream scoop of an excavation. I head for the small exposed vertical face of ironstone. The ground underfoot feels surprisingly hard and uneven. Bracken grows profusely all over Sandy Warren, but not at the bottom of this crater. Peeling back a sliver of moss, my fingers scrape on a bubbled, blackish crust. Close by, I see a lump of iron slag a foot thick, its honeycombed surface bare of vegetation. The chestnut coppice around the rim of the quarry begins to make sense. Was it planted to provide charcoal for a furnace? Stepping back on to the path, I look back down the cutting and my eyes follow the track sweeping round towards the town of Sandy. Our forebears must have dug this V-shaped trackway to carry heavy smelted iron down to the settlement below.